SECRETARY'S REPORT 21 



Services, Dr. Henry W. Setzer, associate curator of mammals, was 

 given a detail in January and February 1953 to proceed to the Canal 

 Zone of Panama to give instruction to members of the 25th Preventive 

 Medicine Survey Detaclmient on the collection and preparation of 

 study specimens of mammals involved in the parasitological and epi- 

 demiological investigations of tropical diseases, and on the comple- 

 tion of this assigmnent he devoted a few days to the study of the fauna 

 of Barro Colorado Island. 



During May and June, Dr. Alexander Wetmore, research associate, 

 assisted by W. M. Perrygo of the National Museum, carried on field 

 studies on the distribution of bird life in Panama in continuation of a 

 program begun several years ago. The work this year covered an area 

 in the southern part of the Province of Veraguas, extending from the 

 National Highway that crosses western Panama down through the 

 great tracts of swampy forest that lie back of the southern coast. The 

 series of specimens obtained give valuable comparative material from 

 an area that previously had been poorly represented in the National 

 Museum collections. Field observations were highly interesting, since 

 the middle of May marked the begiiming of the rains, whereas most 

 of the earlier studies had been made during the dry season of the year. 

 Many of the resident birds exhibit marked difference in habit between 

 the two periods. Though most of the great host of migrant birds from 

 North America that winter here leave for the north by May, numerous 

 records were obtained of several species of which there are groups of 

 younger individuals that have not yet attained breeding status but 

 that remain in these tropical areas through the summer season when 

 the older members are on their northern nesting grounds. Orni- 

 thological fieldwork in Thailand by Herbert G. Deignan was made 

 possible by grants from the Guggenheim Foundation and special 

 research funds of the Smithsonian Institution. He arrived at Bangkok 

 on October 8, 1952, and 12 days later departed for the hills west of 

 that city accompanied by Eobert E. Elbel, Mutual Security Agency, 

 and three native assistants. Collections were made in Kanchanaburi 

 province during October and November. Fieldwork in Prochnap 

 Khiri Khan province, which is situated in southwestern Thailand 

 between the Gulf of Siam and the Tenasserim Mountain range, was 

 completed on December 31, 1952. The field party worked during 

 January 1953 in the mountainous areas of western Nan and northern 

 Lampang provinces on the Thailand-Laos frontier. On February 9, 

 1953, Deignan arrived at Chiang Eai, capital of the northernmost 

 province, and from there proceeded to the Mekong River Valley and 

 made collections at Chiang Saen Kao in the region where the bound- 

 aries of Burma, Thailand, and Indo-China meet. After returning to 

 Bangkok on March 20, Deignan devoted a week to fieldwork in Ratburi 

 province, which is situated betwen the provinces of Kanchanaburi and 



